Manet

Reliable AODV Protocol for Wireless Networking (IEEE-APPL-1074) Ashwin Perti Sr. lecturer Academy of Business and Engineering Scineces, ghaziabad [email protected]

Introduction Types of Misbehavior Metrics & parameters Used Result Conclusion

Introduction Lack of Infrastructure No Central Authority Pivotal role played by the Mobile Nodes are:  Creates  Organize &  Administer the MANET

QoS greatly effects this behaviour

Ad Hoc Network

MANET’s Environment is greatly influenced by these: Hostile Degree Mobility Scenario Traffic load

Node Misbehavior Characteristics Prevention – Line of prevention is build

Detection – detects them but avoids using them in routing

Tolerance – Seeks to work well in their presence

The RAODV uses detection approach

Node Misbehaving Approach After RAODV detects misbehaving nodes, it avoids (isolates) it. Isolation is a security goal RAODV improves the QoS goodput (data delivery Ratio) in all hostile environments & Incurs acceptable routing overhead

Types of Misbehaving Nodes Selfish Nodes – Use the network, but do not cooperate – Time division duplex for send/receive separation Malicious Nodes – Aims at damaging other nodes, – Communication and – Interrupting normal network operation A Malicious node can deploy a variety of Denial-of-Service (DoS) attack.

Malicious Node RAODV deals with the blackmailing problem – A malicious node may blackmail a legitimate node by unjustifiably advertising that this node is misbehaving. This results in other nodes avoiding the legitimate node, which causes the performance to drop. – The RAODV avoids blackmailing without extra authentication or trust management overhead

Comparison with other Related Work Watchdog / path-rater – RAODV is tolerant to black-mailing. A malicious node may blackmail a legitimate node by marking it as misbehaving and reporting it to the source.

BMR (Bypassing Misbehaving nodes Routing) – It is a detection approach able to bypass misbehaving nodes and select a “good” path to route packets – A good path is chosen which is having low loss rate and small delay – It works in 2 phases namely: • The Testing Phase • The Delivery phase

RAODV It is based on the Ad Hoc On-Demand Distance Vector (AODV) routing protocol. It is based on local transparent mechanism to detect and avoid misbehaving nodes at the node level without informing the sender or receiver. In AODV, all routing decisions are taken locally at each forwarding node. No authentication is required since nodes do not communicate in regard to detected misbehaving nodes. The RAODV’s avoidance actions are done locally. RAODV punishes misbehaving nodes by rejecting their routing demands.

Detection Initially all nodes are considered as legitimate node Each node listens to packets sent by nodes within its wireless range When forwarding a data packet to neighbor node (other than the destination node), the node adds an entry for this packet in its pending packet buffer If the timer of an entry in the pending packet buffer expires without the node hearing it being forwarded, (Node is considered as Misbehaving Node)

Avoidance Upon detecting a misbehaving node, the detecting node tries to do local repair for all routes passing through the misbehaving node Different AODV route maintenance Besides avoiding exhausting valuable resources such as bandwidth and battery power, This prevents blackmailing of legitimate nodes

Advantages over other Related Work Unlike the watchdog/path-rater solution, the RAODV is tolerant to black-mailing – A malicious node may blackmail a legitimate by marking it as misbehaving and reporting it to the source – The RAODV’s avoidance actions are done locally; – Watchdog/path-rater lacks the punishment of misbehaving nodes, as these nodes can still send packets. Hence selfish nodes are actually rewarded for their un-cooperation. – RAODV punishes misbehaving nodes by rejecting their routing demands

Advantages over other Related Work By taking an end-to-end point of view, the BMR algorithm provides a unified solution for many node misbehavior – test a path before a packet delivery, resulting in considerable overhead – If a selfish node behaves well during the testing phase and starts to drop the data packets during the delivery phase due to declining resources. – RAODV continuously monitors the node and dynamically adjusting its rating accordingly – BMR makes quite a few security assumptions whereas RAODV makes no assumptions about trust relationships or the behavior of source, destination or other nodes. – BMR requires that each node must have a global unique identifier; which introduces the overhead of identifier allocation and duplicate identifiers detection – Finally a good path model used by BMR only works well under lightlyloaded networks. In the heavily-loaded network, the behaviors of good paths and bad paths can be indistinguishable due to congestion

SIMULATION ENVIRONMENT

Introduction This RAODV protocol is implemented using ns-2 simulator. NS-2 simulator is an event driven simulator – Discrete Event Simulator – Packet level – Link layer and up – Wired and wireless

otcl and C++: The Duality

C++

otcl

C++ for data Otcl for control

Metrics used in Analyzing the RAODV’s performance goodput – Percentage of sent data packets actually received by the intended destinations – The lost (dropped) packets include both those dropped by misbehaving nodes and those dropped for other reasons (e.g. full queue, link errors)

Misbehavior Ratio – ratio of data packets dropped by misbehaving nodes to the number of send data packets

Overhead metric – used to examine the routing packet overhead introduced by the RAODV – Routing packets (RREQ, RREP, RERR, ACK etc) takes very little bandwidth

Important Parameter Parameter

Value

Simulation time

200 seconds

No. of Nodes

100

No. of Misbehaving Nodes

0, 15, 25, 75

No. of Connections

5 or 10

Network Size

670 x 670 sq. meter

Traffic Type

CBR

Sending Rate

4 packets / second

Packet Size

512 bytes (1024)

Maximum Speed

20 meter / second

Pause Time

0, 50, 100 or 200 seconds

RESULTS Traffic Load

Hostility Degree

Metric

Continuous High Mobility Mobility

Low Mobility

goodput

0.07 %

0.23 %

0.02 %

goodput

7%

4%

10 %

goodput

8%

9.5 %

25 %

Safe

goodput

0.5 %

0.44 %

0.02 %

Hostile

goodput

7%

6%

10 %

goodput

8%

12.5 %

25 %

Safe Hostile Light Loaded Very Traffic Hostile

Highly Loaded Traffic Very Hostile

RESULTS Safe Friendly Environment – High mobility is the poorest performer in the lightly loaded traffic – In Overhead, continuous mobility achieves the best result

RAODV performs very well in the highly loaded traffic The continuous mobility scenario gives the best overall results, especially in highly loaded traffic

The low mobility can be used to greatly improve the goodput in lightly loaded traffic.

RESULTS MAC layer (enhanced 802.15.4) – Allows multiple topologies – Reduced functionality devices (RFDs) for the low-power sensor devices – Handle networks with large numbers of devices

CONCLUSION We have proposed and simulated a solution that detects and avoids misbehaving mobile nodes which drop data packets The solution operates transparently by making all the detection and avoidance decisions locally Experimentation results using variations of MANET environments show that the solution improves the goodput by up to 25% with considerably less overhead trade-off compared to other solutions

Thanks